1. Field of the Invention
This invention relates to a method of providing visible marks such as patterns, words, logos or indicia onto an edge of a stack of sheets or leaves, particularly when the sheets or leaves are assembled together in the form of books or pamphlets.
2. Description of the Related Art
U.S. Pat. No. 1,866,968 discloses printing a mark on the face of each page to be assembled into a book. Such that when the assembled pages are cut to size the assembled pages produce a character at the cut edges after cutting. However, the patent does not disclose a method of providing patterns or indicia on the edges of assembled leaves or sheets of paper.
A method of providing indicia on the edges of a plurality of assembled sheets is disclosed in U.S. Pat. No. 4,823,150. In the method disclosed therein, the sheets of material (paper) are assembled into books and the indicia printed by means of an ink-jet printer which places printed marks on the assembled cut edges by dividing said edges into a grid, and selecting the locations on the edges for printing the indicia and then identifying the locations according to the grid, and subsequently programming the printing means to print the marks in accordance with the locations identified by the grid.
Such a method has the disadvantage that the indicia on the edges are printed in a separate operation after the books have been assembled.
Yet another method of providing marks of the edge of a pamphlet is shown in U.S. Pat. No. 4,427,290 which is utilized in photocopiers which are specifically modified for the process.
U.S. Pat. No. 4,949,999 describes a method of indexing books by placing printed symbols on the edges of the leaves. The patent further describes a method of placing (printing) the elements composing the symbols on the individual leaves. However, the patent does not disclose a method of decomposing the symbol to be printed onto the edge of a book into elements corresponding to the pagination of the stacked leaves prior to the actual printing process.
U.S. Pat. No. 3,817,492 illustrates a book wherein each leaf is marked on its face edge prior to cutting the leaf to size and whereby the cut passes through the mark on each leaf. The patent does not disclose a method of obtaining these marks by decomposing the symbol to be provided on the edge of the book into its elements prior to placing the marks onto the leaves.
In the present invention the indicia or indicia on the edges are formed during the printing operation for each respective sheet or leaf in the book. This has the advantage that the system is flexible, cheap, and can be utilized on standard printing equipment when controlled by a microprocessor.